Opponent-driven planning and execution for pass, attack, and defense in a multi-robot soccer team

We present our Small Size League (SSL) robot soccer team, CMDragons, which performed strongly at the RoboCup'13 competition, placing second out of twenty teams after a prolonged final match ending in penalty shoot-outs. We briefly present the robots' hardware and individual skills, and then focus on our multi-robot passing, attack, and defense planning and execution in the challenging SSL adversarial multi-robot environment. We introduce a pass-ahead behavior, as well as a new dynamic two-stage planner, Coerce and Attack, which explicitly considers opponent defense to hypothetical attack patterns. The Coerce stage generates a coerce attack formation to coerce the opponent robots into leaving strategic openings. The Attack stage modifies the coerce attack pattern in a fluid manner to exploit openings in the defense using pass-ahead to attempt to score. We further present our threat-based defensive multi-robot algorithm, which identifies potential threats based on the opponent positioning and plans the defense accordingly. We present the performance of CMDragons at RoboCup'13 in terms of metrics that evaluate the effectiveness of the low-level skills as well as the high-level defense and offense.